This application is a continuation-in-part of U.S. Provisional Patent Application Ser. No. 60/026,485, filed on Sep. 23, 1996.
1. Field of the Invention
The present invention relates generally to apparatus and methods for washing fruits and vegetables, and more particularly, to an improved and simplified apparatus and method for washing plant products and particularly leafy plant products.
2. Description of Related Art
There are a number of devices in the prior art directed toward cleaning fruits and vegetables prior to packaging the fruits and vegetables for the retail marketplace. These devices typically receive newly harvested plant product, then process the plant product for cleaning and performing other processing prior to packaging the plant product for the retail marketplace. These devices typically comprise substantially large, robust pieces of machinery that may be wholly, or partially, automated.
These devices usually include a plant product receiving area for receiving the newly harvested plant products. A processing assembly is typically coupled to the receiving area. The processing area may include a washing assembly, that can include a plant product conveyance assembly containing recirculating water for removing dirt, insecticides, and other undesired particulate matter from the plant products. A drying assembly may optionally be coupled to the washing assembly for drying the cleansed plant products prior to packing the plant product for distribution to retail marketplaces.
A number of such devices are disclosed in the prior art. For example, U.S. Pat. No. 2,467,888, to Harlow, discloses an apparatus for washing plant products. The disclosed apparatus includes a table structure mounted for rotation about an upright axis. The table structure comprises a produce supporting top adapted to retain the produce thereon. The top is coarsely apertured so that when water is sprayed at produce retained on the top, as the water detaches waste from the produce, the apertures are sufficiently large to enable removal of the waste from the table top. The apparatus includes means for spraying the water and means for rotating the table. Further included is a pan that includes separate means for preventing exit of the waste through a water discharge outlet.
U.S. Pat. No. 3,683,945, to Weisser, is directed to a flood cell apparatus for conveying and processing materials for washing conveying, and processing vegetables and the like. The apparatus comprises an inclined tank that has a rounded bottom, a closed inlet end, and an open outlet end. The outlet end is upraised relative to the inlet end to define a flood level over which liquid introduced into the tank, leaves the tank. Nozzles direct streams of water under pressure from the inlet end of the tank toward the outlet end for impelling vegetables toward the outlet end. The nozzles create turbulence in the water for cleaning the vegetables. Waste material is detached from the vegetables and moves toward the inlet end where a waste outlet is provided for removing the waste, while the vegetables are moving toward the outlet end of the apparatus.
Another device for washing produce is disclosed in U.S. Pat. No. 5,413,131, to Medlock. The disclosed washer includes an elongated open top tank that contains water. The tank has a loading end and an opposing exit end. A plurality of outlet nozzles are positioned transversely across the tank and are spaced along the fall length thereof above the water line. A plurality of baffles are positioned in the tank in a staggered arrangement. The nozzles and baffles, along with the water in the tank, coact to draw produce loaded into the tank completely underwater. The produce is moved in an agitating serpentine pattern as it is moved toward the exit end of the tank.
U.S. Pat. No. 3,447,544, to De Vergara, is directed to an apparatus for washing and drying of fruit. The apparatus causes fruit to pass through a series of water baths under the influence of water pressure, under a rinsing spray, and finally between jets of air for drying the fruit.
U.S. Pat. No. 5,097,755, to Hill, discloses a method and apparatus for processing produce, and particularly fresh vegetables for salads. The disclosed apparatus includes a cleaning assembly the includes high pressure nozzles that spray chlorinated water at the desired storage temperature of the vegetables.
U.S. Pat. No. 2,666,711, to Crosset, discloses a method and apparatus for processing leafy vegetables, and particularly for drying leafy vegetables such as spinach. U.S. Pat. No. 4,549,478, to Entes, is directed to an apparatus for washing slices of a tuberous plant, such as potatoes. U.S. Pat. No. 3,918,116, to Valdespino, is directed to a food lift and U.S. Pat. No. 4,509,545, to Trotter, discloses a portable washing and spray assembly.
However, the various methods and apparatus of the prior art have suffer from a number of disadvantages. One disadvantage common to the above enumerated prior art references, and specifically those apparatus directed toward cleaning leafy vegetables, is that they are not well suited for cleaning substantially large volumes of the leafy vegetables. Often as these vegetables are being conveyed along the washing portion of the apparatus, the leafy vegetables collect and clog the washing portion of the apparatus. Unfortunately, operators are needed for monitoring these clogs, which adds to the cost associated with processing of the vegetables.
Another disadvantage found in the prior art, is that as the plant product is conveyed along the washing portion of the apparatus, the plant product is often not completely submerged or not submerged for a sufficiently long time period. This usually results in the plant product not being sufficiently cleansed.
A farther disadvantage of the prior art is that the water spray nozzles spray water under excessive pressure. This often causes the water to contact the plant product with enough force to damage the leaves of the plant products. Additionally disadvantageous of the prior art, is that it is often time consuming to drain and fill the water recirculating through the plant product washing portion of the apparatus. This may cause the water to not be replaced at proper intervals, such as when the water becomes excessively dirty, resulting in the plant product passing through the washing portion not being sufficiently cleaned. Another disadvantage is that these apparatuses are excessively large and consume unnecessary quantities of workspace.
Thus, there exists a need for an improved and simplified apparatus and method for washing plant products and particularly leafy plant product.